Ecologists hopeful after strong year for Everglades wading birds

Great blue heron chicks squawk at each other on Feb. 2, 2018, on the Kissimmee River at Camp Mack’s River Resort in Lake Wales. The South Florida Water Management District reported an above-average 2017 wading bird breeding season.(Photo: Andrew West/The News-Press)

In the heart of the Everglades, where at long last the water levels balanced just right, thousands of great egrets, white ibis, wood storks and other wading birds started to rebound in 2017 from a string of bad nesting seasons.

Many of the birds produced some of their healthiest nests in a decade, fledging tens of thousands of chicks, according to South Florida Water Management District’s annual wading bird report out this month.

It remains to be seen how lasting the uptick will be. And while the birds did well in the refuge of Everglades National Park and in a handful of water conservation areas immediately north of it, they still struggled in their ancient breeding grounds, in the disappearing shallow wetlands near the Big Corkscrew Swamp and coasts of southern Florida, according to the report.

It’s important not to read too much into one-year population jumps or drops, said Mark Cook, the water district’s lead scientist, who helped put together the report.

But last year’s numbers compared to 10- and 20-year averages are a sign for hope, Cook said.

“It shows us ecologists that if we can get the water right in one year and see this kind of rebound then we can restore the system,” he said. “I do not think it’s too far-fetched to say we could recover a good portion of those birds that were historically here, with the right hydrological conditions. Even though the system is about half the size it was, I think it’s possible.”

Buy Photo

A variety of wading birds, from Great egrets and Roseate spoonbills to white ibis and Snowy egrets, can be seen at the Audubon Corkscrew Swamp Sanctuary Sunday, March 12, 2017, in Naples.(Photo: Luke Franke/Naples Daily News)

The district studies the nesting success of wading birds because ecologists believe the species are among the best indicators of the health of the water system. The birds rely on natural patterns of rain and drought, needing long wet seasons for prey fish to multiply and grow in the swamps, followed by dry spells that concentrate those fish into smaller pools to make them easier to catch.

And, thanks to the Audubon Society and old park wardens, they’re one of the few living things with population records that date back to before humans started draining and altering the water flow of the Everglades, Cook said.

“They’re really the only group of organisms that we have good records from the early 20th century and even late 19th century,” he said. “We know where they nested and how many of each species there were. So unlike everything else, we really know what we’re aiming for.”

The population numbers are a far cry from the hundreds of thousands of nests built by the birds, historically. And they are more concentrated in the National Park as the birds continue to be uprooted from their historical breeding grounds near the coasts in places like Big Corkscrew Swamp.

Monitors counted 46,248 wading bird nests in the 2017 season, between December 2016 and July 2017. That’s up from the 26,676 found in 2016 and above the 10-year annual average of 39,066.

It also marks the best year since 2009, the highwater mark for the population since restoration efforts began.

Most species showed better-than-average nesting, but wood storks had the best year. With 3,894 nests, storks almost doubled their 10-year annual average of 2,127.

CLOSE

Dry seasons may cause a feeding frenzy at the Corkscrew Swamp Sanctuary. During this event, wading birds may compete for food from the depleting waters, which will have a higher concentration of fish.
Wochit

Scant few of those nests, however, were built in their age-old breeding ground of Big Corkscrew Swamp near Immokalee. As the shallow wetlands around the swamp have been drained, the federally threatened storks have retreated further inland and north to nest.

So far in 2018, the storks are having one of their better years in Corkscrew, bolstered by extreme events such as the heavy rainfalls that caused massive flooding in the early summer and Hurricane Irma in the fall.

The district’s goal is to have half of stork nests be built in their historical sites near the coasts, and half within the Everglades National Park area, Cook said.

Over the past decade, more than two-thirds of the nests have been built inside the park.

Not all species improved in 2017.

The rroseate spoonbill produced 460 nests, a 19 percent drop from the year before but on par with the 10-year average of 461.

The populations of two smaller species of herons may have declined so much over the past few decades that they may be leaving south Florida for good.

Just 844 nests were built by tricolored herons and 1,341 by snowy egrets. Those mark drops of 18 percent and 54 percent in their 10-year averages.

Posted!

A link has been posted to your Facebook feed.

Buy Photo

A great egret takes a high vantage point as other wading birds, such as white ibis and snowy egrets, meander below at the Audubon Corkscrew Swamp Sanctuary on Sunday, March 12, 2017, in Golden Gate Estates.
Luke Franke/Naples Daily News

A great egret appears to eye its reflection while searching for a morning snack at the Audubon Corkscrew Swamp Sanctuary on Sunday, March 12, 2017, in Golden Gate Estates.
Luke Franke/Naples Daily News

A variety of wading birds, from great egrets and roseate spoonbills to white ibis and snowy egrets, can be seen at the Audubon Corkscrew Swamp Sanctuary on Sunday, March 12, 2017, in Golden Gate Estates.
Luke Franke/Naples Daily News

A variety of wading birds - from great egrets and roseate spoonbills to white ibis and snowy egrets - can be seen at the Audubon Corkscrew Swamp Sanctuary on Sunday, March 12, 2017, in Golden Gate Estates.
Luke Franke/Naples Daily News

A variety of wading birds, from great egrets and roseate spoonbills to white ibis and snowy egrets, can be seen at the Audubon Corkscrew Swamp Sanctuary Sunday, March 12, 2017 in Naples.
Luke Franke/Naples Daily News

A variety of wading birds, from great egrets and roseate spoonbills to white ibis and snowy egrets, can be seen at the Audubon Corkscrew Swamp Sanctuary Sunday, March 12, 2017 in Naples.
Luke Franke/Naples Daily News

A variety of wading birds -- from great egrets and roseate spoonbills to white ibis and snowy egrets -- can be seen at the Audubon Corkscrew Swamp Sanctuary on Sunday, March 12, 2017, in Golden Gate Estates.
Luke Franke/Naples Daily News

A variety of wading birds, from great egrets and roseate spoonbills to white ibis and snowy egrets, can be seen at the Audubon Corkscrew Swamp Sanctuary Sunday, March 12, 2017 in Naples.
Luke Franke/Naples Daily News

A variety of wading birds, from great egrets and roseate spoonbills to white ibis and snowy egrets, can be seen at the Audubon Corkscrew Swamp Sanctuary Sunday, March 12, 2017 in Naples.
Luke Franke/Naples Daily News